An artist's impression of the Osiris-REX craft near the asteroid Bennu. Picture: NASA For Martin George space column for Hobart MercurySource:Supplied

A HISTORIC space mission is due to skim across Australia’s skies early tomorrow morning and if you’ve got a telescope or a good camera lens, you should be able to watch it blaze a path over our continent.

Since being launched in September last year, NASA’s OSIRIS-REx spacecraft has been racing around the sun at an average speed of 100,800km/h.

But it’s about to make a close approach to Earth so it can use our planet’s gravitational pull to gather speed before slingshotting itself towards an asteroid called Bennu.

This isn’t the first time a spacecraft has used what’s known as a gravity assist manoeuvre. The first time the famed Hollywood move was used was for a US space probe called the Mariner 10 which launched in 1973.

But what makes this unique is just how close the OSIRIS-REx is going to be to the Earth when it does its fly-by and Australia happens to have a front-row seat with some of the closest views.

The spacecraft will zip overhead at a minimum distance of 17,000km which is about 22 times closer than the moon.

“It’s not going to be visible to the naked eye, but really any amateur astronomer with a half decent telescope should be able to do it,” said Phil Bland from Curtin University in Western Australia, who will be watching the event unfold.

“Or a big lens on a regular camera like a telephonic lens, they should be able to pick it up and see it themselves.”

The apparent pathway of the OSIRIS-REx spacecraft over Australian skies will take an hour, beginning over Rockhampton in Queensland at 00.22am local time on September 23 and exiting over Adelaide at 00.53am local time.

While those directly under the flight path (such as people in Rockhampton or Adelaide) will get the best view, many people in Australia’s east will be able to see it, depending on the strength of their telescope.

This shows the expected path of the NASA craft which will fly overhead after midnight.Source:Supplied

Professor Bland is a member of the OSIRIS-REx science team and also leads an Australian group called the Desert Fireball Network, which, as he puts it, “tracks fireballs coming through the atmosphere.”

The project helps answer some fundamental questions about the origin of celestial materials that land on Earth.

“We don’t know where meteorites comes from,” Prof Bland told news.com.au last week. Basically, we’ve got all these samples that land on Earth but we don’t know the journey they took to get here. “So what we try to do with the fireball network, we track everything that comes through the atmosphere over a large fraction of Australia,” he said.

Automated observatories dotted across the country monitor anything that blazes through the sky, which gives astronomers a good idea of where meteorites will land and roughly where they came from in the solar system.

“It’s kind of like giving us a geological map of the solar system,” Prof Bland said.

The OSIRIS-REx mission has a similar objective and will give us unprecedented insight into the early formation of our solar system.

The OSIRIS-REx spacecraft sits on its workstand August 20, 2016. Picture: Bruce WeaverSource:AFP

After the slingshot manoeuvre, the OSIRIS-REx spacecraft will take about another year to reach the asteroid Bennu, where the real work begins.

Once there it will spend about 12 months on the surface of the space rock, mapping and analysing the asteroid before embarking on its return journey.

If all goes according to plan, it will return to Earth in 2023 carrying a sample from carbon rich asteroid which could help us record the early history of the solar system and better understand the molecular precursors to the origin of life.

“One of the reasons we want to go to the asteroid is that these materials haven’t really been altered that much since the solar system formed, so they can tell us a lot about how planets came together,” Prof Bland said. “There’s a lot of really big questions we don’t have the answer to for that.”